This invention relates to a filter to be provided for the gasoline tank in an automobile.
As is well known, the suction pipe for drawing gasoline from the gasoline tank is provided at the tip thereof with a filter adapted to prevent impurities from being entrained by the gasoline being drawn. Such filters heretofore known in the art are mostly of a type having a net stretched along the periphery thereof. In the upper lid for closing the upper opening of the filter body, an insertion hole is perforated, through which the suction pipe may be passed to be thrust into the interior of the filter body. The pipe is tightly attached to the insertion hole so as to prevent the filter from coming off the tip of the pipe. To render this attachment stable and constant, there is generally followed the practice of providing a bulged portion on the periphery at a stated position in the entire length of the pipe, causing the bulged portion to be forcibly pushed into engagement with the edge of the insertion hole, and enabling the insertion hole to keep firm hold of the pipe in consequence of the forced engagement.
The conventional filter, as viewed from the standpoint of its relation with the suction pipe, therefore, has no noticeable problem because it is attached easily and retained fast in the attached state. As viewed from the standpoint of its relation with the gasoline tank, however, the filter has one problem yet to be solved.
To be specific, the suction pipe is required to draw the gasoline completely from the gasoline tank and, in this respect, is desired to have the tip thereof reach the bottom of the gasoline tank. The pipe fitted with the filter, therefore, is disposed within the gasoline tank in such a manner that the bottom of the filter may come into contact with the bottom of the tank. In the mass production of gasoline tanks and suction pipes to be inserted into the gasoline tanks, although they are manufactured in standard sizes fixed in advance, gasoline tanks and suction pipes so produced rarely fail to function due to errors of fabrication to some extent. It is not unlikely, therefore, that some suction pipes will not be fixed at a stated position within gasoline tanks because the bottoms of their filters are stopped short of advancing to their full depths owing to their collision with the bottom surfaces of tanks and some other suction pipes will be suspended within gasoline tanks because their filters fall short of reaching the bottom surfaces of tanks. It has been difficult for all the produced suction pipes to be disposed accurately in a fixed state within the produced gasoline tanks.